Extending Roof Rafters For Insulation

The roof rafters are currently about 20 apart made of 2x6 s the house was built in 1915.

Extending roof rafters for insulation. How to extend rafters. Hack n stack sealed foam board between the rafters would be better since it s at least an air impermeable insulation but even that would require a vent gap below the roof deck to meet code and you d still be under r38 on that 2x6 rafters unless you. Arguably the most popular pitched roof solution installing insulation between and under the rafters uses the depth of the structural timbers to best effect. Almost there with the old fo.

Apply insulation between rafters when finishing an attic into a heated room or when building a cathedral ceiling in the home. In finished attic rooms with or without dormer insulate 2a between the studs of knee walls 2b between the studs and rafters of exterior walls and roof 2c and ceilings with cold spaces above. Images courtesy simpson gumpertz heger. An efficient room in a roof in a new build property where over rafter insulation is not desirable.

After a bit more destruction and dust it is time to look at how we increased the rafter depth in preparation for the insulation. Garages built without attics are. Roof insulation configurations for unvented rafter truss assemblies. The outer ends of a roof s rafters the sloped members that give the roof its pitch provide shade divert rain and create soffit space for attic ventilation.

Batts between rafters in would require adding ventilation between the insulation roof deck. Its versatility is the key to its popularity whether being used to achieve. By installing high density 8 inch fiberglass batt insulation the rafters will then meet an r 30 roof insulation standard. For instance if the roof has 2 by 6 rafters and you want r 30 insulation which is standard in many communities you can add a 2 by 4 which will give you an 9 inch rafter space.

2d extend insulation into joist space to reduce air flows.